This invention relates to roof panel seamers and, more particularly, to a roof panel seamer which is self-propelled and bidirectional for forming a standing seam joining two adjacent metal roof panels.
Roof panel seamers have been used for many years to join, or connect, a pair of adjacent metal roof panels having abutting vertical portions, where one of the vertical portions is terminated by an outturned female flange portion with a downturned terminal portion forming a U-shaped channel, and the other of the vertical portions is terminated by an inturned male flange portion positioned in the U-shaped channel of the one vertical portion. The resulting seam has either a ninety degree (90°) or a one hundred eighty degree (180°) profile. Forming the 90° seam is called the first stage, and forming the 180° degree seam from a previously formed 90° seam is called the second stage.
The two different basic types of seamers presently available are the single stage electric seamer which seams just one stage seam per seaming machine but can seam in both directions, and the double stage electric seamer which seams both the first and second stage seams in a single pass but only in one direction. These seamers are limited in their speed because they are only able to use a small drill motor for drive power due to weight limitations, so the only way to increase the speed is to improve the efficiency by which the seam is formed. It is therefore an object of this invention to improve seam forming efficiency.
Seamers are two-part devices. There is a main support body, which contains the drive mechanism, and an auxiliary support body which is movable toward and away from the main support body to allow the seamer to be mounted on the panels to be seamed. Seaming is effected by a series of roll forming stations, each roll forming station having components mounted on both the main and auxiliary bodies. Prior art seamers used gearing to transfer drive power from the main body to the auxiliary body. A problem therefore arose when the main and auxiliary bodies were separated and then rejoined because the gearing first became disengaged and then had to be reengaged. It is therefore another object of this invention to eliminate such gearing while still being able to transfer drive power from the main body to the auxiliary body.
Prior art seamers were designed with the forming tooling located along with the drive rollers. Because of this, the spacing of the forming tooling, due to the size of the drive rollers, limited the number of roll forming stations that could be accommodated to keep the machines small and the weight of the machines low. Consequently, the 90° and 180° seams were each formed with two roll forming stations, which limited the ability to form the seam efficiently. It is therefore a further object of this invention to improve the efficiency by which the seams are formed without increasing the size of the machine.
Prior art seamers used to form a 90° seam used straight angled forming rollers at progressive angles to rotate the seam through its 90° rotation. This often resulted in the bent leg not being properly seated, which could interfere with proper operation of the second stage (i.e., 180°) seamer. It is therefore yet another object of this invention to improve seam formation in a first stage seamer.